I wrote to the organization an email yesterday asking why the three hours seminar has been reduced to one hour talk without any previous notice, and having just five working days to react. In fact, I don't even have known it from them, but reading the program!

No response.

I could understand they did a wrong estimation, or they forgot the time accorded for my seminar when assigning holes in the table, or they just did a mistake. No problem. But no response? Not even a courtesy reply? Is this serious?